Needed fix for Drupal 11

This seems to work

 protected function retrieveUncachedJwks(string $url) {
    $local_path = $this->generateLocalCachePath($url);

    $data = (string) \Drupal::httpClient()->get($url)->getBody();
    dpm($data);
    $file =  \Drupal::service('file.repository')->writeData($data, $local_path, FileSystemInterface::EXISTS_REPLACE);

    return $file->getFileUri();

/** @noinspection PhpUnnecessaryLocalVariableInspection
$saved_path =
system_retrieve_file(
$url,
$local_path,
FALSE,
FileSystemInterface::EXISTS_REPLACE
);

return $saved_path;
*/

}